JP2002164797A - High output voltage controlled oscillator - Google Patents

Abstract

(57) [Summary] To provide a high output voltage controlled oscillator with low power loss. SOLUTION: An input terminal 11 to which a control voltage is input,
A voltage controlled oscillating unit 14 to which a control voltage input to the input terminal 11 is supplied, and a power amplifier formed by connecting an output of the voltage controlled oscillating unit 14 and a plurality of amplifier circuits connected in series. A power amplifier 17 and an output terminal 18 to which an output of the power amplifier 17 is supplied. The voltage controlled oscillator 14 and at least the first-stage amplifier circuit 19 of the power amplifier 17 are formed by balanced amplifier circuits. Since a balanced / unbalanced conversion circuit is provided in the power amplifier 17, a high output voltage controlled oscillator with less power loss can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a high output voltage controlled oscillator used for a portable telephone or the like.

[0002]

2. Description of the Related Art A portable telephone using a conventional voltage controlled oscillator will be described below. As shown in FIG. 3, a mobile phone using a conventional voltage-controlled oscillator is:
An antenna 1, an antenna switch 2 connected to the antenna 1, and a surface acoustic wave (hereinafter, referred to as SAW) filter 3 connected to one terminal of the antenna switch 2.
A demodulator and modulator 5 including a low-noise amplifier (hereinafter referred to as LNA) 4 to which the output of the SAW filter 3 is connected; a control circuit 6 for a mobile phone connected to the demodulator and modulator 5 A voltage controlled oscillator 7 connected to the outputs of the demodulator and modulator 5, a power amplifier 8 connected to the output of the voltage controlled oscillator 7, and a power amplifier 8 connected to the other terminal of the antenna switch 2. And a low-pass filter 9 connected to the power supply.

The operation of the portable telephone constructed as described above will be described below. The signal input from the antenna 1 passes through the SAW filter 3, is amplified by the LNA 4, and is demodulated by the demodulator and the demodulator of the modulator 5.
The output is controlled by the control circuit 6 and displayed on the display unit, and is output as an audio output.

A signal input from a keyboard and a voice input from a microphone are input to and controlled by a control circuit 6, and the output is modulated by a demodulator and a modulator of a modulator 5. Then, the output is converted into a carrier by the voltage controlled oscillator 7, and the output is power-amplified by the power amplifier 8 and input to the low-pass filter 9. In this low-pass filter 9, harmonics were removed, and the output was emitted from the antenna 1 through the antenna switch 2.

Here, a voltage controlled oscillator 7 and a power amplifier 8
In order to avoid interference from outside, a balanced circuit shown in FIG. 4 was used. In this case, it is necessary to provide a balance-unbalance conversion circuit 10 between the power amplifier 8 and the low-pass filter 9.

[0006]

However, if such a balanced / unbalanced conversion circuit 10 is provided, a loss of about 1.0 dB is inevitably generated by the balanced / unbalanced conversion circuit 10. 2. Description of the Related Art In mobile phones and the like, a large output is desired as much as possible while saving power. In a mobile phone or the like that requires such performance, arranging the balanced / unbalanced conversion circuit 10 after the final output of the power amplifier 8 once having a large power deteriorates power efficiency. Cannot satisfy the required performance.

An object of the present invention is to solve such a problem and to provide a high output voltage controlled oscillator with high power efficiency.

[0008]

In order to achieve this object, a high output voltage controlled oscillator according to the present invention comprises an input terminal to which a control voltage is input, and a voltage to which the control voltage input to the input terminal is supplied. A control oscillating unit, a power amplifying unit to which an output of the voltage control oscillating unit is supplied and a plurality of amplifying circuits connected in series, and a power amplifying signal to which an output of the power amplifying unit is supplied. An output terminal, wherein at least the first-stage amplifier circuit of the voltage controlled oscillator and the power amplifier is formed by a balanced amplifier, and a balanced / unbalanced conversion circuit is provided in the power amplifier. Outputs an unbalanced signal.

Thus, a high output voltage controlled oscillator with high power efficiency can be obtained.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS According to the first aspect of the present invention, there is provided an input terminal to which a control voltage is input, a voltage controlled oscillator to which the control voltage input to the input terminal is supplied, A power amplifying unit formed by supplying an output of the control oscillation unit and a plurality of amplifying circuits connected in series;
An output terminal of a power amplification signal to which an output of the power amplification unit is supplied, wherein at least the first-stage amplification circuit of the voltage control oscillation unit and the power amplification unit is formed by a balanced amplification circuit and is provided in the power amplification unit. A balanced / unbalanced conversion circuit is provided, and the power amplifier is a high output voltage controlled oscillator that outputs an unbalanced signal. Since the output of the final power amplifier is output as an unbalanced signal, It is not necessary to connect a balanced / unbalanced conversion circuit to the output of the device. Therefore, there is no power loss due to the balanced / unbalanced conversion circuit, and power saving can be achieved.

Further, since the voltage controlled oscillator and at least the first-stage amplifier circuit of the power amplifier are formed by balanced amplifier circuits, they are less likely to be disturbed by external signals.

According to a second aspect of the present invention, the power amplifying unit includes three
2. The high-output voltage controlled oscillator according to claim 1, wherein the balanced / unbalanced conversion circuit is provided in the first-stage amplification circuit, and the balanced / unbalanced conversion circuit is provided in the first-stage amplification circuit. Since it is provided and performs balanced / unbalanced conversion in the state of a small signal, power loss is small and power saving can be achieved.

According to a third aspect of the present invention, there is provided the high output voltage controlled oscillator according to the first aspect, wherein the voltage controlled oscillator and the power amplifier are integrated in one package. This facilitates handling and management. In addition, the size can be reduced.

According to a fourth aspect of the present invention, there is provided the high output voltage controlled oscillator according to the third aspect, comprising a two-system voltage controlled oscillator and a power amplifying unit. It can be used for multi-band mobile phones and the like.

According to a fifth aspect of the present invention, there is provided a high output voltage control according to the third aspect, further comprising a radiator plate thermally connected to the power amplifying unit, and the radiator plate is led out as a terminal of the package. Since this is an oscillator, a large heat sink can be attached to the outside via this terminal, so that heat dissipation characteristics can be improved, and as a result, power saving can be achieved.

According to a sixth aspect of the present invention, the terminal derived from the heat sink is formed on the side surface of the package and has a larger size than the other terminals. This is a controlled oscillator, and the terminal itself can have heat radiation characteristics. Further, since the terminals are formed on the side surfaces of the package, surface mounting becomes possible.

According to a seventh aspect of the present invention, there is provided the high output voltage controlled oscillator according to the sixth aspect, wherein a ground signal of the power amplifier is connected to a terminal led out from the heat sink. In addition to this terminal, it is hardly affected by external noise.

The invention according to claim 8 has a radiator plate thermally connected to the power amplification unit, and the radiator plate is provided on the bottom surface of the package so as to be solderable from the outside. Since it is a high output voltage controlled oscillator and a large heat sink is attached, heat dissipation characteristics are improved. Further, since this heat radiating plate is provided so as to be solderable from the outside, a second heat radiating plate can be provided outside, and the heat radiating characteristics are further improved.

According to a ninth aspect of the present invention, there is provided the high output voltage controlled oscillator according to the eighth aspect, wherein a ground signal of a power amplifier is connected to a heat sink provided on a bottom surface of the package. Can be omitted and the terminal is less susceptible to external noise.

According to a tenth aspect of the present invention, there is provided the high output voltage controlled oscillator according to the third aspect, wherein the ground of the voltage controlled oscillator and the ground of the power amplifier are led out of the package independently. Since the grounds are separated from each other, they are hardly affected by each other and can sufficiently exhibit their respective performances.

According to an eleventh aspect of the present invention, the power amplifying unit is a high output voltage controlled oscillator according to the first aspect, wherein the amplification degree can be controlled from the outside, and the output power is controlled by a difference in communication distance. For example, in the case of short-distance communication, the power amplification can be reduced to save power.

According to a twelfth aspect of the present invention, there is provided the high output voltage controlled oscillator according to the first aspect, wherein the voltage controlled oscillator and the power amplifier are formed of SiGe. In spite of the fact that the performance is substantially the same, a remarkably low price can be realized.

According to a thirteenth aspect of the present invention, the voltage controlled oscillating unit and the power amplifying unit are respectively integrated in separate packages, the voltage controlled oscillating unit is formed of SiGe, and the power amplifying unit is formed of GaP. The high output voltage controlled oscillator according to claim 1, wherein the voltage controlled oscillator and the power amplifier can be produced by different technologies, respectively, so that the yield is good and the productivity is improved. Further, since the yield is good, the price can be reduced.

According to a fourteenth aspect of the present invention, the two series of voltage controlled oscillators and power amplifiers are integrated in respective packages, and these packages are mounted on one printed circuit board. The high-output voltage-controlled oscillator described above is a multi-band high-output voltage-controlled oscillator, and can be used for a multi-band mobile phone and the like.

An embodiment of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is a block diagram of a high output voltage controlled oscillator according to Embodiment 1. In FIG. 1, reference numeral 11 denotes an input terminal to which a control voltage is input,
It is connected to a balanced amplification circuit 13 via a resonance circuit 12. The output of the balanced amplifying circuit 13 is connected to the output terminal 15 as the output of the voltage-controlled oscillating unit 14 and to the power amplifying unit 17 via the matching circuit 16. The output of the power amplifying unit 17 is connected to the output terminal 1
8 is connected.

The power amplifier 17 includes amplifier circuits 19, 20,
21 are connected in series in this order. The amplifier circuit 19 amplifies a signal of approximately +5 dBm (approximately 3 mW) to approximately 20 dBm. The next amplifier circuit 20 amplifies the signal to approximately 30 dBm, the next amplifier circuit 21 amplifies the signal to approximately 36 dBm (approximately 4 W), and outputs the amplified signal to the output terminal 18. In the conventional device, an output of approximately 1.0 dBm is reduced from a final output of 36 dBm amplified to a large power by a balanced / unbalanced conversion circuit. However, in the present invention, since the balanced / unbalanced conversion circuit is provided in the first-stage amplifier circuit 19, the signal of approximately 36 dBm output from the output terminal 18 needs to be attenuated by the balanced / unbalanced conversion circuit as in the prior art. There is no. Therefore, finally, approximately 36 dBm from the antenna of a mobile phone or the like remains unchanged.
Is output.

Reference numeral 22 denotes a power control terminal, which controls the amplification degree of the amplifier circuit 19, the amplifier circuit 20, or the amplifier circuit 21 by a signal input from the power control terminal 22. As a result, as a result, the output power of the power amplification unit 17 is arbitrarily controlled. This is to control the output power according to the difference in communication distance. For example, in the case of short-distance communication, power consumption can be reduced by lowering the power output level to lower the current consumption of the amplifier circuit 21.

In this embodiment, the amplifier 19 has a built-in balanced / unbalanced conversion circuit. Therefore, the amplifier circuits 20 and 21 after the amplifier circuit 19 are unbalanced amplifier circuits. With this configuration, the output from the output terminal 18 becomes an unbalanced signal, and there is no need to insert a balanced-unbalanced conversion circuit having a loss of about 1.0 dBm as in the related art.

The voltage controlled oscillator 14 is formed by a balanced resonance circuit 12 and a balanced amplification circuit 13. The matching circuit 16 and the first-stage amplifier circuit 19 are also formed by balanced circuits.

The voltage controlled oscillator 14 and the power amplifier 1
In the case where 7 is formed by SiGe (silicon-germanium) technology, a low-priced one having substantially the same performance as that formed by conventional gallium arsenide can be realized.

The input terminal 11, the output terminals 15, 18 and the power control terminal 22 are led out to the side surface of the package 23 to enable surface mounting.

(Embodiment 2) FIG. 2 is a block diagram of a high output voltage controlled oscillator according to a second embodiment of the present invention. The high output voltage controlled oscillator for GSM which outputs a frequency of 900 MHz and a frequency of 1800 MHz are used. D to output
High output voltage controlled oscillator for CS and one package 3
0. Therefore, if this high output voltage controlled oscillator is used, a two-band mobile phone can be easily realized.

The configuration will be described below. 31 is GSM
And a GSM and a DSM provided in the package 30 via a low-pass filter 32.
It is input to the input terminal 33 of the control voltage common to CS. The control voltage input to the input terminal 33 is connected to a balanced amplifier 35 via a resonance circuit 34. The output of the balanced amplifier circuit 35 is input to the phase detector 31 via the output terminal 36 as the output of the voltage controlled oscillator. The output of the balanced amplifier 35 is connected to a power amplifier 38 via a matching circuit 37. The power amplifying unit 38
Are connected to an output terminal 39 of GSM. Note that the power amplifying unit 38 includes three amplifying circuits 40, 41, and 42 connected in series similarly to the first embodiment.
Then, balanced amplification is performed. The balanced amplifying circuit 40 has a built-in balanced / unbalanced conversion circuit.

Reference numeral 43 denotes a DCS band phase detector.
The output is supplied to the package 3 via the low-pass filter 32.
0 is input to an input terminal 33 of a common control voltage for GSM and DCS. Hereinafter, since the configuration is the same as that of GSM, the description will be simplified by adding a suffix a.

Reference numeral 44 denotes a power control circuit. The output of the power control circuit 44 is connected to the first-stage amplifier circuits 40 and 40a or 41 and 41a and further to 42 and 42a to control the amplification degree. . The power control circuits 40, 41,
The amplification degree 42 can be controlled from the power control terminal 45 as in the first embodiment. Also, output terminal 3
Couplers 46, 4 provided on the lines derived from 9, 39a
6a is for monitoring the output power.

47 and 47a are power amplifiers 38 and 38a
And a radiator connected thermally to the ground of the power amplifiers 38 and 38a. This heat radiation part 47,
47a is led out to the side of the package 30. The heat radiating portions 47 and 47a may be provided on the bottom surface of the package 30 or may be connected to the parent substrate.

This high output voltage controlled oscillator for GSM and D
Terminals to the outside of the CS high output voltage controlled oscillator are provided at symmetric positions of the package 30 as shown in FIG. By arranging in this manner, it is easy to route the pattern on the parent substrate.

(Embodiment 3) The voltage controlled oscillator and the power amplifier may be integrated in separate packages. In this case, the voltage controlled oscillator is SiGe (silicon.
The power amplifier can be formed by GaP (gallium / phosphorus) or GaN (gallium / chisso) technology.

By using such a technique, the voltage controlled oscillator and the power amplifier can be produced by different techniques, respectively, so that the yield is good and the productivity is improved. Further, since the yield is good, the price can be reduced.

Also, the two-system voltage controlled oscillator and power amplifier are integrated in respective packages, and when these packages are mounted on one printed circuit board, a multi-band high-output voltage-controlled oscillator becomes It can be used for mobile phones and the like.

[0042]

As described above, according to the present invention, at least the first-stage amplifier circuit of the voltage controlled oscillator and the power amplifier is formed by a balanced amplifier and a balanced / unbalanced converter is provided in the power amplifier. Provided, an unbalanced signal is output from the power amplification unit, and the output of the final power amplification circuit is output as an unbalanced signal. Therefore, a balanced / unbalanced conversion circuit is connected to the output of the power amplification unit. do not have to. Therefore, there is no power loss due to this balanced / unbalanced conversion circuit,
Power saving can be achieved.

Further, since the voltage controlled oscillator and at least the first-stage amplifier circuit of the power amplifier are formed by balanced amplifier circuits, they are less likely to be disturbed.

[Brief description of the drawings]

FIG. 1 is a block diagram of a high output voltage controlled oscillator according to a first embodiment of the present invention.

FIG. 2 is a block diagram of a high output voltage controlled oscillator according to the second embodiment.

FIG. 3 is a block diagram of a mobile phone using a conventional voltage-controlled oscillator.

FIG. 4 is a block diagram of the voltage controlled oscillator and the power amplifier.

[Explanation of symbols]

 11 Input Terminal 14 Voltage Controlled Oscillator 17 Power Amplifier 18 Output Terminal 19 Amplifier 20 Amplifier 21 Amplifier

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 5J081 AA01 CC11 CC44 EE01 FF04 GG05 KK03 KK16 KK22 MM01 5J091 AA01 AA41 CA36 CA41 CA87 FA15 HA38 KA00 KA13 KA29 KA32 KA42 KA53 KA55 KA64 KA65 KA01 MA01 SA08 DD04 HH06 HH26 LL07

Claims (14)

[Claims] 1. An input terminal to which a control voltage is input, a voltage controlled oscillator to which the control voltage input to the input terminal is supplied, and a plurality of amplifiers to which an output of the voltage controlled oscillator is supplied. A power amplifying unit formed by connecting circuits in series, and an output terminal of a power amplifying signal to which an output of the power amplifying unit is supplied, wherein at least a first-stage amplification of the voltage controlled oscillator and the power amplifying unit is provided. A high output voltage controlled oscillator, wherein the circuit is formed by a balanced amplifier circuit, a balanced / unbalanced conversion circuit is provided in the power amplifier, and an unbalanced signal is output from the power amplifier. 2. The high output voltage controlled oscillator according to claim 1, wherein the power amplifying section is formed by a three-stage amplifier circuit, and the first-stage amplifier circuit is provided with a balanced / unbalanced conversion circuit. 3. The high output voltage controlled oscillator according to claim 1, wherein the voltage controlled oscillator and the power amplifier are integrated in one package. 4. The high output voltage controlled oscillator according to claim 3, further comprising a two-series voltage controlled oscillator and a power amplifier. 5. The high output voltage controlled oscillator according to claim 3, further comprising a heat radiator thermally connected to the power amplifying unit, wherein the heat radiator is led out as a terminal of the package. 6. The high output voltage controlled oscillator according to claim 5, wherein the terminal led out from the heat sink is formed on a side surface of the package and is larger in size than the other terminals. 7. The high output voltage controlled oscillator according to claim 6, wherein a ground signal of the power amplifier is connected to a terminal led out from the heat sink. 8. The high output voltage controlled oscillator according to claim 3, further comprising a heat radiator thermally connected to the power amplifying unit, wherein the heat radiator is provided on a bottom surface of the package so as to be solderable from outside. 9. The high output voltage controlled oscillator according to claim 8, wherein a ground signal of the power amplifier is connected to a heat sink provided on a bottom surface of the package. 10. The high output voltage controlled oscillator according to claim 3, wherein the ground of the voltage controlled oscillator and the ground of the power amplifier are led out of the package independently of each other. 11. The high output voltage controlled oscillator according to claim 1, wherein the power amplification section is capable of externally controlling the amplification degree. 12. The voltage controlled oscillator and the power amplifier are composed of SiG
2. The high output voltage controlled oscillator according to claim 1, formed of e. 13. The voltage controlled oscillator and the power amplifier are integrated in separate packages, respectively, the voltage controlled oscillator is formed of SiGe, and the power amplifier is formed of Ga.
2. The high output voltage controlled oscillator according to claim 1, wherein the oscillator is formed of P. 14. The high output voltage controlled oscillator according to claim 13, wherein the two series of voltage controlled oscillators and power amplifiers are integrated in respective packages, and these packages are mounted on one printed circuit board.